Patent US3666562A successfully refreshed from Google Patents.
US3666562A
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US
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Fuel cell with control system and method
Assignee: VARTA AG
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Filing: 1969-03-03
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Granted: 1972-05-30
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Expires: 1989-03-03
Abstract
Abstract A CONTROL SYSTEM IS PROVIDED FOR IMPROVING THE VENTING OF ACCUMULATED INERT GAS FROM ELECTROCHEMICAL ENERGY CONVERSION MEANS SUCH AS FUEL CELL BATTERIES. THE VENTING PERIOD IS INITIATED BY A DROP IN CELL POTENTIAL BUT IS INDEPENDENT OF CELL POTENTIAL RECOVERY TIME.
Inventors
- 👤 Dietrich Sprengel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 03:27
CPC Classifications
H; H01; H01M; H01M8/00; H01M8/04; H01M8/04298; H01M8/04313; H01M8/04537; H01M8/04544; H01M8/04559; H01M8/04694; H01M8/04746; H01M8/04761; H01M8/24; H01M8/2457; H01M8/04223; H01M8/04231; Y; Y02; Y02E; Y02E60/00; Y02E60/30; Y02E60/50
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-30 | 1975-11-29 | 1976-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-30 | 1979-11-29 | 1980-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-30 | 1983-11-29 | 1984-05-30 | $7700.00 | Window Closed / Lapsed |